Amazon (NASDAQ:AMZN | AMZN Price Prediction) and Microsoft (NASDAQ:MSFT) both filed earnings on April 29, 2026, framing two different bets on the AI buildout. Amazon leans on custom silicon and, per a $25 billion multi-tranche bond sale, to fund infrastructure. Microsoft leans on its OpenAI stake and contracted backlog. Same tailwind, different balance sheets.
AWS Reaccelerates While Azure Sprints Ahead
Amazon posted EPS of $2.78 against a $1.653 estimate on revenue of $181.52 billion, up 16.61%. AWS grew $37.59 billion in revenue, growing 28%, the fastest pace in fifteen quarters, at a 37.7% operating margin. Ads cleared $70 billion trailing, a real second engine.
Microsoft delivered EPS of $4.27 versus $4.09 expected on $82.89 billion in revenue, up 18.3%. Azure grew 40% (39% constant currency), and the AI business hit $37 billion annual run rate, up 123%. Commercial remaining performance obligations reached $627 billion, nearly doubling year-over-year, contracted demand years out.
| Business Driver | Amazon | Microsoft |
| Cloud growth | AWS +28% | Azure +40% |
| Q1 CapEx | $44.2B | $30.88B |
| Operating margin | 11.2% | 45.6% |
Custom Silicon Vs. Contracted Compute
Andy Jassy said Amazon’s chips business is at $20 billion run rate with triple-digit growth, with total Trainium commitments reaching over $225 billion, including up to 5 GW from Anthropic and 2 GW from OpenAI starting in 2027. Jassy expects Trainium to save “tens of billions of dollars of CapEx each year”.
Microsoft’s leverage is contractual. Satya Nadella framed the quarter around delivering “cloud and AI infrastructure and solutions” for the agentic era. Microsoft leans heavily on NVIDIA silicon and its OpenAI partnership, enormously profitable but leaving less optionality on chips than Amazon has built.
The Capex Bill Is About To Get Louder
Amazon’s TTM free cash flow collapsed 95% to $1.2 billion, and long-term debt jumped to $119.1 billion from $65.6 billion. Polymarket traders assign 87.5% probability that 2026 capex tops $200 billion, with a coin-flip on $220 billion or more. Microsoft’s CapEx surged 84.39% year-over-year, and management stayed quiet on numeric guidance. I want to see whether AWS margins hold as this cash deploys.
Why I’m Leaning Toward Amazon Right Now
Since the reports, AMZN is down 6.49% and MSFT is down 8.19%. Neither has been rewarded. Amazon’s ability to tap institutional debt cheaply, pair it with a chip stack customers are pre-buying in gigawatts, and still show 29.6% operating income growth on core business tilts the read. Microsoft is a fantastic compounder at 45.6% operating margin, and if you want quality and dividend support, that case is intact. But if custom silicon is the real moat of this cycle, Amazon looks like the fortress trade. I would change my view if AWS margin slips below the mid-30s while capex keeps climbing.
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